The object of the present invention is a device for the impact cooling of the turbine packing rings of a turbojet engine.
In known devices, the packing rings of a turbine are cooled by means of the relatively cold air issuing from an upstream stage of the compressor or taken from the cooling air of the combustion chamber. This air flows, for example, into an enclosure concentric with respect to the packing rings through regularly distributed orifices drilled into a radial flange of the turbine housing. At the outlet of the orifices, part of this air impacts the walls of the turbine housing, another part escapes through the clearance between the turbine housing and a low pressure distributor and finally, a third part passes through perforated plates separate from the surface of the rings for the impact cooling of the rings prior to returning to the stream of the driving fluid. However, the turbulence prevailing in the enclosure concentric with the packing rings acts to perturb the flow of air intended to cool the packing rings, thus interferring with the supply of air to the holes into the perforated plates.